In a 2-1 split, the Federal Circuit affirmed a nonobviousness determination in a contentious dispute between medical technology companies. The case turned on the construction of the claim term “treating a wound” – specifically, the meaning and scope of “wound.” The majority adopted the Plaintiff-Cross Appellants’ definition of “wound” as meaning only surface tissue damage, rejecting the Defendant-Appellants’ argument that the “plain and ordinary meaning” of the term would include some kinds of internal damage. Judge Dyk dissented because he would have interpreted the term more broadly.

PatentlyO provides a brief recap, noting that this case highlights how unpredictable claim construction, which is required in nearly every patent case, can be.

Kinetic Concepts, Inc. and others (collectively “KCI”) sued Blue Sky Medical Group, Inc. and others (collectively “Blue Sky”) for claims including infringement of KCI’s patents (U.S. Patent Nos. 5,636,643 and 5,645,081), which relate to treatment of wounds. Blue Sky counterclaimed that KCI’s patents were invalid and unenforceable. The jury returned a verdict that the asserted patents were not shown to be invalid or unenforceable, although it found against KCI on their infringement and other claims. Blue Sky appealed.

On appeal, Blue Sky adopted a broad construction of the claim term “wound,” relying on medical dictionaries to establish ordinary meaning. KCI rejected the broad interpretation as beyond “the scope of the specification,” opting instead for a narrow definition that limited “wound” to “tissue damage to the surface of the body, including the epithelial and subcutaneous layers.” The defendant’s construction, KCI argued, would lead to absurd application, since it would necessarily include “‘conditions such as ruptured appendices and stomach ulcers’ that the specification in no way suggests can be treated according to the claimed invention.”

In her majority opinion, Judge Prost adopted a narrow construction of the word “wound,” concluding that, as used in the asserted patents, it did not cover the “fistulae” and “pus pockets” described in prior art references. She rejected Blue Sky’s contention that regardless of which claim construction is used, prior art references disclosed “treating wounds with negative pressure.” Concluding that the testimony of KCI’s witnesses provided the jury with a sufficient basis to determine that the prior art did not teach or suggest KCI’s technique, the court affirmed the jury’s verdict of nonobviousness.

Judge Dyk dissented, criticizing the majority on two major grounds: first, for limiting the claim term “wound” to “the disclosed embodiments in the specification” and second, for misreading the specification as showing only treatments of surface or skin wounds. He argued that the majority’s claim construction was unsupported by medical dictionary or extrinsic evidence, and concluded that the majority instead improperly used the specification examples to limit the claim.Judge Dyk’s would have instead relied on the medical dictionary definition of “wound” to construe the claim to include fistulae caused by surgical incision. Under his claim construction he found that there was “uncontroverted evidence” of obviousness; thus, the asserted claims of U.S. Patent Nos. 5,636,643 and 5,645,081 would have been obvious.

Harold Wegner, in a commentary on ipFrontline.com, characterized the ruling as representative of the problematic American approach to claim construction.“Unlike the United Kingdom and Germany,” he notes, “the American system . . . places emphasis on the specification to interpret the scope of protection as opposed to confirmation of the meaning of the claim.” Wegner concludes that panel splits “as manifested in Kenetic Concepts” are “difficult if not impossible to avoid.” In the absence of an exhaustive study of the record, it is “possible that both constructions are acceptable.” Wegner argues that the outcome in Kenetic Concepts highlights the “continued imperative of statutory claim construction reform.”